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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="core.typeinfo"></a><a class="link" href="typeinfo.html" title="typeinfo">typeinfo</a>
</h2></div></div></div>
<div class="toc"><dl class="toc"><dt><span class="section"><a href="typeinfo.html#core.typeinfo.header_boost_core_typeinfo_hpp">Header
      &lt;boost/core/typeinfo.hpp&gt;</a></span></dt></dl></div>
<div class="simplesect">
<div class="titlepage"><div><div><h3 class="title">
<a name="idm14237"></a>Authors</h3></div></div></div>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
          Peter Dimov
        </li></ul></div>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="core.typeinfo.header_boost_core_typeinfo_hpp"></a><a class="link" href="typeinfo.html#core.typeinfo.header_boost_core_typeinfo_hpp" title="Header &lt;boost/core/typeinfo.hpp&gt;">Header
      &lt;boost/core/typeinfo.hpp&gt;</a>
</h3></div></div></div>
<p>
        The header <code class="computeroutput"><span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">core</span><span class="special">/</span><span class="identifier">typeinfo</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
        defines a class <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">typeinfo</span></code>, which is an alias for <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">type_info</span></code>
        when RTTI is enabled, and is a reasonable substitute when RTTI is not supported.
      </p>
<p>
        The macro <code class="computeroutput"><span class="identifier">BOOST_CORE_TYPEID</span></code>,
        when applied to a type <code class="computeroutput"><span class="identifier">T</span></code>,
        is the equivalent of <code class="computeroutput"><span class="keyword">typeid</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span></code>
        and produces a reference to a const <code class="computeroutput"><span class="identifier">typeinfo</span></code>
        object.
      </p>
<p>
        The function <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">demangled_name</span></code> takes a <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">typeinfo</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">ti</span></code> and either returns <code class="computeroutput"><span class="identifier">ti</span><span class="special">.</span><span class="identifier">name</span><span class="special">()</span></code>,
        when that string doesn't need to be demangled, or <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">demangle</span><span class="special">(</span><span class="identifier">ti</span><span class="special">.</span><span class="identifier">name</span><span class="special">())</span></code>,
        when it does. The return type of <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">demangled_name</span></code>
        is <code class="computeroutput"><span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span></code> in the first case and <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>
        in the second.
      </p>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="core.typeinfo.header_boost_core_typeinfo_hpp.synopsis"></a><a class="link" href="typeinfo.html#core.typeinfo.header_boost_core_typeinfo_hpp.synopsis" title="Synopsis">Synopsis</a>
</h4></div></div></div>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span>
<span class="special">{</span>

<span class="keyword">namespace</span> <span class="identifier">core</span>
<span class="special">{</span>
    <span class="keyword">class</span> <span class="identifier">typeinfo</span><span class="special">;</span>
    <span class="comment">/* char const* or std::string */</span> <span class="identifier">demangled_name</span><span class="special">(</span> <span class="identifier">typeinfo</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">ti</span> <span class="special">);</span>
<span class="special">}</span>

<span class="special">}</span>

<span class="preprocessor">#define</span> <span class="identifier">BOOST_CORE_TYPEID</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span> <span class="comment">/*unspecified*/</span>
</pre>
</div>
<div class="section">
<div class="titlepage"><div><div><h4 class="title">
<a name="core.typeinfo.header_boost_core_typeinfo_hpp.example"></a><a class="link" href="typeinfo.html#core.typeinfo.header_boost_core_typeinfo_hpp.example" title="Example">Example</a>
</h4></div></div></div>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">core</span><span class="special">/</span><span class="identifier">typeinfo</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">iostream</span><span class="special">&gt;</span>

<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T1</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">T2</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">X</span>
<span class="special">{</span>
<span class="special">};</span>

<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
<span class="special">{</span>
    <span class="keyword">typedef</span> <span class="identifier">X</span><span class="special">&lt;</span><span class="keyword">void</span> <span class="keyword">const</span><span class="special">*,</span> <span class="keyword">void</span><span class="special">(*)(</span><span class="keyword">float</span><span class="special">)&gt;</span> <span class="identifier">T</span><span class="special">;</span>

    <span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">typeinfo</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">ti</span> <span class="special">=</span> <span class="identifier">BOOST_CORE_TYPEID</span><span class="special">(</span><span class="identifier">T</span><span class="special">);</span>

    <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">demangled_name</span><span class="special">(</span> <span class="identifier">ti</span> <span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
<span class="special">}</span>
</pre>
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<td align="right"><div class="copyright-footer">Copyright © 2014 Peter Dimov<br>Copyright © 2014 Glen Fernandes<br>Copyright © 2014 Andrey Semashev<p>
        Distributed under the <a href="http://boost.org/LICENSE_1_0.txt" target="_top">Boost
        Software License, Version 1.0</a>.
      </p>
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